### What problem does this PR solve?

Fix: Optimize the MultiSelect component and system prompt templates
#3221

- Modify the conditional statements in the MultiSelect component, using
the ?. operator to improve code readability
- Optimize the formatting of the system prompt template to make it more
standardized and easier to read
- Update the Chinese translation, changing "ExeSQL" to "Execute SQL"

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

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Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>